Denture



E. F. NELSON March 22, 1949;

DENTURE 2 Sheets-Sheet 1 Filed Jan. 24, 1947 v'll. j u

I INVEN-TOR.'

March 22, 1949. NELSON 2,464,987

I DENTURE Filed Jan. 24, 1947 2 Sheets-Sheet 2 INVENTOR.

Patented Mar. 22, 1949 UNITED STATES PATENT OFFICE 4 Claims.

The present invention relates to artificial teeth, and more particularly to dentures.

Among the proposals that have been made to overcome the dissatisfaction with present-day methods of mounting dentures has been to clamp the denture mechanically at isolated buccal and lingual areas of the wearers gum.

An object of the present invention is to provide a new and improved denture.

Other and further objects will be explained hereinafter and will be particularly pointed out in the appended claims.

With these ends in view, a feature of the invention resides in a fluid-containing chamber provided with a flexible wall or face for engaging the gum. Because of its flexibility, the wall or face yieldingly conforms to the surface of the gum with which it engages, and the fluid pressure behind the wall or face becomes thus equally distributed throughout the area of engagement.

The invention will now be more fully explained in connection with the accompanying drawings, in which Fig. 1 is an elevation, partly in section, of upper and lower dentures of the roof type embodying the invention, shown in place in the mouth; Fig. 2 is a section, upon a larger scale, taken on the line 2-2 of Fig. 1, looking in the direction of the arrows; Fig. 3 is a section similar to Fig.2, with the parts in relatively different positions; Fig. 4 is a fragmentary section similar to Fig. 1, but upon a larger scale, of a modification; Fig. 5 is an elevation similar to Fig. 1, but upon a larger scale, of the upper denture, shown detached, parts being shown in section; Fig. 6 is a similar view, with the parts in relatively different positions; Fig. 7 is a fragmentary perspective, upon a still larger scale, with the parts occupying the relative positions shown in Fig. 2; Fig. 8 is a similar fragmentary perspective, with the parts occupying the relative positions shown in Fig. 3; and Fig. 9 is a perspective of an upper denture of the roofless type, upon approximately the same scale as in Fig. 1.

Upper and lower dentures l and 2 of the roof type are shown in Fig. 1, respectively held in place on upper and lower gums 8. Each denture may be of the usual bridge-work or dental-plate type, channel-shaped or U-shaped in cross section. The side faces or the arms of the channel or the U are adapted to engage the opposite buccal and lingual surfaces of the gum 8, and the artificial teeth .are carried on the outer ridge of the channel, constituting the'neck of the U. The dentures are each shown enclosing the gum 8 throughout the extent of the gum, from a .pos-

The stationary part of this molar is shown pro-- vided with stationary projections ll, hereinafter referred to. The movable part of this molar, indicated at. B, is fixed to a hinge 5, shown as a spring-metal plate, that is anchored to the denture l or 2. The bias introduced by the spring- L metal plate or other hinge 5 tends to maintain the molar part 6 in what may be termed an ineli'ective or open position, as illustrated in Figs. 3, 6 and 8. For convenience, the molar part 6 may be referred to as the molar.

Clo-sing movement of the jaws toward each other will result in pivotal movement of the molars 5 of the two dentures I and 2 from the inefiective or open positions toward what may be termed their effective or closed positions, illustrated in Figs. 1, 2, 5 and '7. The pivotal movement of each molar 6 toward its effective or closed position is guided, so as to prevent wobbling, by a lug [6, carried by the next-adjacent molar, entering a correspondingly shaped slot l5 in the molar 6, and by the before-mentioned stationary projections ll engaging against inner walls I8 of the molar 5, as illustrated more particularly in Fig. 3. A spring catch it, shown in Figs. '7 and 8, but omitted from the other figures for clearness, rides over the outer buccal face of the molar 5 during its pivotal movement toward the effective or closed position. Upon the molar 6 reaching its effective or closed position, the spring catch l9 snaps into a recess i l in the said buccal face to hold the molar 6 against accidental displacement. For clarity, this recess 14, like the spring catch I0, is shown in Figs. '7 and 8 only.

In the effective or closed position of each molar 6, an inside face 9 thereof presses against the outer flexible wall 22 of a chamber 4, in order to impose pressure upon fluid, such as air or water, contained therein. The chamber 4 is shown uncompressed in Figs. 3, 6 and 8, and compressed in Figs. 1, 2, 5 and 7. The fluid in the chamber 4 becomes thus forced through a conduit 28 into the space 3 of a flexible-walled tubular chamber '1 that communicates with the chamber d. The conduit Zfland the tube 1 are shown extending continuously throughout the peripheral extent of the gum 8, from one of the posterior molar teeth 6, forward along one of the sides of the gum 8, to its front part, and then back along the other side of the gum 8, to the other posterior molar tooth 6. One of the side walls of the tube 7, which may be termed the outer side wall !9, is shown conforming in shape to the shape of a semi-cylindrical wall II of the denture I or 2. It is flxed to the wall I I in any desired manner, as by means of a suitable adhesive, or by molding it integrally with the wall II. The other or inner side wall 25 of the tube I, however, is free to flex into contact with the adjacently disposed side of the gum 8. At least this inner side 25 of the tube I, therefore, should be suitably flexible. It is shown extending throughout the periphery of the arm of the U or channel of the denture.

The flexible walls of the fluid-containing chamber may be constituted of any suitable material. Rubber, however, has certain disadvantages. It is therefore proposed to employ a suitable flexible plastic, such as a suitably plasticized vinyl resin polymer,

The ingredients of this compound should be in suitable proportions such as to render the tube I sufliciently flexible so as to conform to the shape of the gum 8, yet sufliciently tough to withstand the stresses imposed upon it in use.

To reduce the tendency for air or other ases to permeate through the walls of the chamber, the inner faces of these walls may be coated, as shown at 26, with a solution of a polyvinyl alcohol polymer. This coating may be supplied in any desired manner, as by spraying, painting or dipping.

The flexible fluideontainin chamber need not, however, be constituted entirely of the plasticized polymer, and it need not be of uniform constitution or thickness. It is preferred, as before stated, that least the inner side wall 25 of the tube 3, that engages the gum 3, be constituted of this flexible substance, in order that it may conform readily, throughout its extent, to the shape of the gum, the surface of which it engages.

The chamber 4, the conduit 28 and the tube I may be sealed in any desired way, mechanical or electrical, in order that they may together constitute a sealed container for the fluid. The travel of the fluid from the chamber 4, through the conduit 28, into the tube l, in response to the fluid pressure produced by the inside face 9 of the molar ii upon the flexible wall 22 of the chamber 4, when the molar is actuated toward its effective or closed portion, therefore results in flexing the free flexible inner side wall 25 of the tube "l snugly into tight engagement with the adjacent surface of the gum 8. This engagement produces uniform and even pressure throughout the extent of the periphery of the gum 8. Though this pressure is heavy enough to hold the denture in place on the gum 3, it is sufficiently light so as not to produce ischemia and consequent gangrene. It will be understood that the showing of the drawings, according to which the inner side wall 25 of the tube 2' bulges into a depression in the gum 8, is exaggerated, for illustrative purposes. A very effective denture is thus provided that may be very effectively held in place on the gum 8, and that may nevertheless be worn in perfect comfort, without any harmful effects whatever.

The upper roof-type denture l is shown provided with only a single tube 7, the flexible wall of which engages the buccal surface of the upper gum 8. The lower roof-type denture 2, however, and the upper roofless-type dentures 26 are each shown provided with two tubes 1, respectively engaging against the buccal and the lingual surfaces of the lower gum 8. The pressure exerted on one side of the gum 8 by even the single tube I is alone sufficient to hold the denture in place, for it is balanced by the pressure of the denture on the other side of the gum 8. Where two tubes I are employed, however, the pressure exerted by one of them, on one surface of the gum 8, is balanced by the pressure exerted by the other tube I on the other surface.

The tubes I are shown of relatively small diameter compared to the depth of the channel or U. of the denture I or 2. It is found that a diameter of 4 inch or less is quite suflicient for the purpose of holding the denture very effectively in place. If it is desired to distribute the pressure exerted by the flexible walls of the tube I over a larger area, of course, the diameter of the tubes I may be correspondingly increased. The expedient illustrated in Fig. 4, may, however, be employed. According to the modification of this Fig. l, instead of cementing in place the outer wall of a tube I, the space 3 bounded by the wall II is merely covered by a flexible flat strip 2| to seal the space 3 along its side edges I2. The strip 2| may be constituted of the same before-described plasticized vinyl or other resin.

When it is desired to remove the denture from the mouth, the spring catch IE1 is released from its slot I4 by slipping the finger nail into a recess I 3 on the molar 6, behind the free end of the spring catch It]. The spring-metal plate or other hinge 5 thereupon actuates the molar 6 from the effective or closed position, illustrated in Figs. 1, 2, 5 and 7, to the inefiective or open position of Figs. 3, 6 and 8. This releases the fluid pressure upon the flexible walls of the tubes I or the strip 2|.

In connection with both the roof and roofless types of denture, the binding action is augmented by the suction produced through the exclusion of air in the space between the gum 8 and the denture.

In all cases, as the bearing pressure of the flexible wall 25 of the tube 1 is distributed throughout its length, the pressure exerted thereby upon the surface of the gum 8 is uniform throughout; without concentration upon any particular part of the surface of the gum, as has been the case heretofore with the mechanically proposed clamping devices.

Further modifications will occur to persons skilled in the art, and all such are considered to fall within the spirit and scope of the present invention, as defined in the appended claims.

What is claimed is:

1. A denture comprising a tooth-carrying member having a gum-engaging face provided with a flexible portion separated from the body of the tooth-carrying member by a space, the toothcarrying member having a flexible-walled chamber connected with the space by a conduit, the chamber, the conduit and the space being sealed to constitute a sealed fluid container, and means controlled by pressure exerted by a tooth carried by the tooth-carrying member for exerting pressure upon a flexible wall of the chamber to force fluid under pressure from the chamber through the conduit into the space to force the flexible portion into tight engagement with the gum.

2. A denture comprising a tooth-carrying memher having a gum-engaging face provided with a flexible portion separated from the body of the tooth-carrying member by a space, the toothcarrying member having a flexible-walled chamber connected with the space by a conduit, the chamber, the conduit and the space being sealed to constitute a sealed fluid container, and one of the teeth carried by the tooth-carrying member having a portion movable into and out of pressure-exerting contact with a flexible Wall of the chamber in order that the fluid pressure thereby exerted upon the said flexible wall by the movable portion of the said tooth may be communicated through the conduit to the space to force the flexible portion into tight engagement with the gum.

3. An artificial-tooth structure comprising a tooth-carrying member, an artificial tooth movably mounted on the tooth-carrying member, means for guiding the movement of the tooth on the tooth-carrying member, and a spring catch displaceable in response to the guided movement of the tooth to ride along the side of the tooth during its guided movement, the tooth having a recess into which the spring catch is received at the limit of its guided movement, and the spring catch cooperating with the recess and the guiding means to maintain the tooth in position on the tooth-carrying member.

4. An artificial-tooth structure comprising a tooth-carrying member, a spring plate fastened to the tooth-carrying member, an artificial tooth carried by the spring plate, the plate being adapted to hold the tooth in a first position on the tooth-carrying member, the tooth being movable to a second position on the tooth-carrying member, and means for holding the tooth in the second position in opposition to the action of the spring plate.

ELLIS F. NELSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS OTHER REFERENCES Pages 640-647 of publication Journal American Dentistry, vol. 29, April 1942. (Copy in Class 32-2, Division 55.) 

